Cutting back or mowing off weeds is sometimes used to control weeds in the garden or lawn. Timely or frequent cutting back stresses the weed and reduces its competitive advantage over more desirable plants. Consistent removal of the upper portion of a weed, especially a perennial weed, will prevent weeds from shading nearby desirable plants and slow the growth of the weed.
Weeds typically grow back from the root system. Rarely will the weed be killed by mowing or cutting back alone. When weeds are cut back before they flower and set fruit, it can significantly reduce seed production and reduce new weeds from emerging. This is particularly helpful for annual weeds that persist year to year by starting from new seeds each season – fewer seeds means fewer weeds in the future.